Furnace with which blister copper of 96-98% purity is obtained.
The process consists of a first stage called slag blowing, where the oxidation of the sulphur and a slag with a significant amount of copper are obtained. In a second stage, copper blowing, where the blister copper is finally achieved and it’s deposited in the bottom due to its greater density.
It needs a refractory with low porosity to avoid the infiltration of the copper oxides and with a resistance to abrasion by the intense movement of the broth.